October 12, 2023 – Cambodia has reported two fatal cases of human infection with the HPAI (highly pathogenic avian influenza) H5N1 avian influenza A virus. This is the third and fourth case of human infection with the H5N1 influenza virus reported in Cambodia this year. The infected patients lived in two different provinces, and the two cases most likely occurred due to exposure to infected poultry. Cases of sudden deaths of poultry due to the H5N1 avian influenza virus have been reported in some areas of Cambodia recently, so it is not surprising that sporadic cases of human infection with the H5N1 avian influenza virus have occurred. Investigations are ongoing to try to confirm the source of infection and identify other cases that may be occurring.
Two fatal infections in Cambodia involved a child and an adult, both of whom had been exposed to poultry before becoming ill. These infections were detected through the Influenza Alert and Surveillance System. One of the patients developed severe symptoms at an influenza sentinel surveillance hospital, and another died in hospital, triggering the alert of the local rapid response team. Close contacts of both patients, including potentially exposed health care workers, are being closely monitored. So far, there is no indication that the two human cases of H5N1 virus pose a threat to the American public.
Genetic sequencing of patient samples by the Institut Pasteur of Cambodia (IPC) and the National Institute of Public Health of Cambodia (NIPH) identified the viruses as H5 clade 2.3.2.1c, which has been circulating in Cambodian birds/poultry for many years . These viruses have previously caused sporadic infections in humans, including two cases in Cambodia in February 2023. The H5 clade 2.3.2.1c virus in Cambodia is different from the H5 viruses causing outbreaks in wild and poultry in the United States. joined.
The CDC is working with the Cambodian Ministry of Health’s Division of Communicable Disease Control (C-CDC), the Cambodian National Institute of Public Health, the Ministry of Agriculture, Forestry and Fisheries, the IPC, the World Health Organization, the FAO, and the Wildlife Conservation Society to investigate these cases. respond. We will provide updates as new information becomes available.